Conventional air-fuel delivery systems can be broadly divided into two types: Carburetion and fuel injection. The carburetion system only permits the use of light fuel oil and is becoming increasingly complex in mechanism because of the need to meet the recent emission control requirements with the consequential increase in cost. Fuel injection for Diesel engines employs a fuel pump for compressing air and, at the point of maximum compression, fuel oil is injected into the combustion chamber and ignition takes place as a result of the high temperature which has been created. In electronic fuel injection, the fuel injectors are essentially solenoid actuated on/off poppet valves incorporating pintles designed for metering and atomization of light fuel oil, which requires precision in machining and becomes costly in mass production.
Fuel injection operating on the principle of electrostatic attraction and repulsion as described in copending U.S. patent application Ser. No. 778,944 filed on Mar. 10, 1977 and assigned to the same assignee of the present invention, is advantageous over the prior art fuel injection in that the disclosed fuel injection permits the use of both light and heavy fuel oils, is simple in construction and easy to regulate the amount of fuel to be injected.